Loading, Outage & Weight Limits
11 free questions, part of the Tanker (N) Endorsement CDL practice test
Outage is the empty space you deliberately leave at the top of a cargo tank so the liquid has room to expand as it warms up. You should never load a tank completely full, and how much outage you need depends on the liquid, the temperature, and legal weight limits. ELDT.io's free bank has 11 practice questions on this.
Ready for the real requirement? Class A CDL Theory theory training is $15, reported to the FMCSA registry instantly.
Start Class A CDL Theory ($15)Questions about Loading, Outage & Weight Limits
Why can't I just fill the tank all the way to the top?
Liquid expands as it warms, and a completely full tank has nowhere for that expansion to go, which can push liquid out of the vents or overpressure the tank. Outage leaves room for that expansion.
Why would I load a dense liquid like an acid below the tank's full physical capacity?
Dense liquids weigh more per gallon, so filling the tank to its physical limit could put you over legal weight limits before the tank is even full. The CDL manual points to temperature, outage requirements, and weight limits as the three factors that determine how much to load.